London was once awash with apprentices. They poured into the city from across the country: at Elizabeth I’s death, they made up over 10 per cent of the entire city population. Fifty years and a civil war later, London had doubled in size, and historians estimate that a quarter of its population had at some point served an apprenticeship. Apprentices lived as well as trained with their apprenticeship masters. They often made trouble and quite often rioted. They also became skilled journeymen and often employers in their turn, either in London or back in the provinces. The whole system feels surprisingly like the modern university sector, in which young people move en masse across the country, seeking degrees as the passport to good jobs, and with the pull of London as strong as ever. Or rather, the two did feel similar, until very recently. Because in today’s uncertain economy, degrees are losing their glitter. The average “graduate premium” — the amount that a degree adds to your...